Rust not mentioned in documentation + `make deps build` fails

Describe the bug

The documentation does not inform users that cargo and rust dependencies are needed to build ocaml-tree-sitter when running make deps build.

Even when rust version 1.49.0 is installed, the following error occurs:

nicolas@localhost:~/nicobao/caramel$ make deps build
opam install dune menhir ocaml-compiler-libs cmdliner ppx_sexp_conv sexplib ocamlformat bisect_ppx
[NOTE] Package bisect_ppx is already installed (current version is 2.5.0).
[NOTE] Package ocamlformat is already installed (current version is 0.15.0).
[NOTE] Package sexplib is already installed (current version is v0.14.0).
[NOTE] Package ppx_sexp_conv is already installed (current version is v0.14.1).
[NOTE] Package cmdliner is already installed (current version is 1.0.4).
[NOTE] Package ocaml-compiler-libs is already installed (current version is v0.12.3).
[NOTE] Package menhir is already installed (current version is 20201216).
[NOTE] Package dune is already installed (current version is 2.7.1).
dune build @all -j8
         gcc ocaml-tree-sitter/tests/sexp_parser.o (exit 1)
(cd _build/default/ocaml-tree-sitter/tests && /usr/lib64/ccache/gcc -O2 -fno-strict-aliasing -fwrapv -fPIC -D_FILE_OFFSET_BITS=64 -D_REENTRANT -O2 -fno-strict-aliasing -fwrapv -fPIC -g -I /home/nicolas/.opam/default/lib/ocaml -I ../src -o sexp_parser.o -c sexp_parser.c)
sexp_parser.c:1:10: fatal error: tree_sitter/parser.h: No such file or directory
    1 | #include <tree_sitter/parser.h>
      |          ^~~~~~~~~~~~~~~~~~~~~~
compilation terminated.
       bootc src/stdlib/beam/beam.{cma,cmi},src/stdlib/beam/binary.{cma,cmi},src/stdlib/beam/calendar.{cma,cmi},src/stdlib/beam/caramel_runtime.{cma,cmi},src/stdlib/beam/erlang.{cma,cmi},src/stdlib/beam/ets.{cma,cmi},src/stdlib/beam/io.{cma,cmi},src/stdlib/beam/lists.{cma,cmi},src/stdlib/beam/maps.{cma,cmi},src/stdlib/beam/process.{cma,cmi,erl},src/stdlib/beam/timer.{cma,cmi}
Compiling maps.erl  OK
Compiling ets.erl   OK
Compiling erlang.erl    OK
Compiling calendar.erl  OK
Compiling binary.erl    OK
Compiling io.erl    OK
Compiling process.erl   OK
       cargo ocaml-tree-sitter/src/dllocaml_tree_sitter.so,ocaml-tree-sitter/src/libocaml_tree_sitter.a (exit 101)
(cd _build/default/ocaml-tree-sitter/src && /home/nicolas/.cargo/bin/cargo build --target-dir ../../target)
    Updating crates.io index
    Updating git repository `https://github.com/AbstractMachinesLab/tree-sitter-sexp`
   Compiling cc v1.0.66
   Compiling memchr v2.3.4
   Compiling proc-macro2 v1.0.24
   Compiling unicode-xid v0.2.1
   Compiling syn v1.0.58
   Compiling lazy_static v1.4.0
   Compiling regex-syntax v0.6.22
   Compiling anyhow v1.0.37
   Compiling ocaml-sys v0.19.0
   Compiling cty v0.2.1
   Compiling thread_local v1.1.0
   Compiling aho-corasick v0.7.15
   Compiling quote v1.0.8
   Compiling tree-sitter v0.17.1
   Compiling tree-sitter v0.17.1 (/home/nicolas/nicobao/tree-sitter/lib)
   Compiling tree-sitter-sexp v0.1.0 (https://github.com/AbstractMachinesLab/tree-sitter-sexp?branch=main#b46b9f78)
   Compiling regex v1.4.3
   Compiling synstructure v0.12.4
   Compiling ocaml-derive v0.19.0
   Compiling ocaml v0.19.0
   Compiling ocaml-tree-sitter v0.1.0 (/home/nicolas/nicobao/caramel/_build/default/ocaml-tree-sitter)
error[E0603]: module `ffi` is private
   --> src/lib.rs:147:53
    |
147 |     let raw_lang = raw_ptr.0 as *const tree_sitter::ffi::TSLanguage;
    |                                                     ^^^ private module
    |
note: the module `ffi` is defined here
   --> /home/nicolas/nicobao/tree-sitter/lib/binding_rust/lib.rs:1:1
    |
1   | mod ffi;
    | ^^^^^^^^

error[E0603]: tuple struct constructor `Language` is private
   --> src/lib.rs:148:29
    |
148 |     let lang = tree_sitter::Language(raw_lang);
    |                             ^^^^^^^^ private tuple struct constructor
    | 
   ::: /home/nicolas/nicobao/tree-sitter/lib/binding_rust/lib.rs:34:21
    |
34  | pub struct Language(*const ffi::TSLanguage);
    |                     ---------------------- a constructor is private if any of the fields is private
    |
note: the tuple struct constructor `Language` is defined here
   --> /home/nicolas/nicobao/tree-sitter/lib/binding_rust/lib.rs:34:1
    |
34  | pub struct Language(*const ffi::TSLanguage);
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

error: aborting due to 2 previous errors

To Reproduce

Install the rust toolchain : https://www.rust-lang.org/tools/install
Run make deps build in the root directory of the repository

Expected behavior

The build should succeed.

Desktop (please complete the following information):

OS: Fedora 33 [x86_64]
rust version 1.49.0
opam version 2.0.7
make version 4.3
dune version 2.7.1

Additional information

Content of ocaml-tree-sitter/Cargo.toml was modified:

[package]
name = "ocaml-tree-sitter"
version = "0.1.0"
authors = ["Leandro Ostera <leandro@ostera.io>"]
edition = "2018"

[lib]
crate-type = ["staticlib", "cdylib"]

[dependencies]
anyhow = "*"
ocaml = "*"
tree-sitter =  { path = "/home/nicolas/nicobao/tree-sitter/lib" }
tree-sitter-sexp = { git = "https://github.com/AbstractMachinesLab/tree-sitter-sexp", branch = "main" }

The tree-sitter dependency corresponds to my local fork of tree-sitter. If i use "*" instead of { path = "/home/nicolas/nicobao/tree-sitter/lib" }, I get the same error.

leostera / caramel

Rust not mentioned in documentation + `make deps build` fails #40